1    /* 
2     * A program to paint an abstract gradient in the vertical direction. 
3     */
4    
5    package npw;
6    
7    import painter.SPainter;
8    import shapes.SCircle;
9    
10   import javax.swing.*;
11   import java.awt.*;
12   import java.util.Random;
13   import java.util.Scanner;
14   
15   public class SimpleDots {
16   
17       public static void main(String[] args) {
18           SwingUtilities.invokeLater(SimpleDots::new);
19       }
20   
21       public SimpleDots() {
22           paintTheImage();
23       }
24   
25       private void paintTheImage(){
26           // Grab the input information
27           int width = getNumber("width");
28           int height = getNumber("height");
29           int dotSpace = getNumber("horizontal space between dots");
30           String colorOfDots = getColor("circle colors");
31           // Establish the painter
32           SPainter painter = new SPainter("Simple Dots", width, height);
33           SCircle dot = new SCircle(5);
34   
35           // Move the painter to the upper left corner to get ready to paint the gradient
36           painter.mfd(height/2.0);
37           painter.tl();
38           painter.mfd(width/2.0);
39           painter.tl();
40   
41           // Paint it!
42           paintGradient(painter, dot, height, width, dotSpace, colorOfDots);
43       }
44   
45       private String getColor(String prompt) {
46           String era = JOptionPane.showInputDialog(null,prompt+"?");
47           Scanner scnner = new Scanner(era);
48           return scnner.next();
49       }
50   
51       private static int getNumber(String prompt) {
52           String nss = JOptionPane.showInputDialog(null,prompt+"?");
53           Scanner scanner = new Scanner(nss);
54           return scanner.nextInt();
55       }
56   
57       private void paintGradient(SPainter painter, SCircle dot, int height, int width, int dotSpace, String colorOfDots){
58           // Calculate the number of columns. We want to fill the screen, but don't want any columns half on the canvas.
59           // A column takes up the horizontal space of a dot's diameter plus the space between it and a neighbor.
60           double colWidth = dot.diameter() + dotSpace;
61           // We don't want a column all the way on the edge on the right side, so subtract 1.
62           int nrOfCols = (int) Math.floor(( width / colWidth )) - 1;
63   
64           int cols = 0;
65           while (cols < nrOfCols){
66               nextCol(painter, dot, dotSpace);
67               paintColumn(painter, dot, height, dotSpace, colorOfDots);
68               cols = cols + 1;
69           }
70       }
71   
72       private void paintOneDot(SPainter painter, SCircle dot, String colorOfDots){
73           painter.setColor(paintColor(colorOfDots));
74           painter.paint(dot);
75       }
76   
77       private Color paintColor(String colorOfDots) {
78           if (colorOfDots.equalsIgnoreCase("blue")) {
79               return Color.BLUE;
80           }
81           if (colorOfDots.equalsIgnoreCase("red")) {
82               return Color.RED;
83           }
84           if (colorOfDots.equalsIgnoreCase("green")) {
85               return Color.GREEN;
86           }
87           else {
88               return Color.BLACK;
89           }
90       }
91   
92       private Color randomColor() {
93           Random rgen = new Random();
94           int r = rgen.nextInt(256);
95           int g = rgen.nextInt(256);
96           int b = rgen.nextInt(256);
97           return new Color(r,b,g);
98       }
99   
100      // Dots are spaced more tightly together near the bottom of the canvas.
101      private void paintColumn(SPainter painter, SCircle dot, int height, int dotSpace, String colorOfDots) {
102          int totalDistanceTraveled = 0;
103  
104          // Paint a column with decreasing distance between dots.
105          while(totalDistanceTraveled < height - (dot.radius() * 3)) {
106              int travel = dotSpace;
107              totalDistanceTraveled = totalDistanceTraveled + travel;
108              painter.mfd(travel);
109              paintOneDot(painter, dot, colorOfDots);
110          }
111  
112          // Make the method invariant with respect to painter position.
113          painter.mbk(totalDistanceTraveled);
114      }
115  
116      // Moves the painter to the next column.
117      private void nextCol(SPainter painter, SCircle dot, int dotSpace){
118          painter.tl();
119          painter.mfd(dot.diameter() + dotSpace);
120          painter.tr();
121      }
122  
123  }
124